src/stdio/vfwprintf.c

   1 #include "stdio_impl.h"
   2 #include <errno.h>
   3 #include <ctype.h>
   4 #include <limits.h>
   5 #include <string.h>
   6 #include <stdarg.h>
   7 #include <wchar.h>
   8 #include <inttypes.h>
   9
  10 /* Convenient bit representation for modifier flags, which all fall
  11  * within 31 codepoints of the space character. */
  12
  13 #define ALT_FORM   (1U<<'#'-' ')
  14 #define ZERO_PAD   (1U<<'0'-' ')
  15 #define LEFT_ADJ   (1U<<'-'-' ')
  16 #define PAD_POS    (1U<<' '-' ')
  17 #define MARK_POS   (1U<<'+'-' ')
  18 #define GROUPED    (1U<<'\''-' ')
  19
  20 #define FLAGMASK (ALT_FORM|ZERO_PAD|LEFT_ADJ|PAD_POS|MARK_POS|GROUPED)
  21
  22 #if UINT_MAX == ULONG_MAX
  23 #define LONG_IS_INT
  24 #endif
  25
  26 #if SIZE_MAX != ULONG_MAX || UINTMAX_MAX != ULLONG_MAX
  27 #define ODD_TYPES
  28 #endif
  29
  30 /* State machine to accept length modifiers + conversion specifiers.
  31  * Result is 0 on failure, or an argument type to pop on success. */
  32
  33 enum {
  34         BARE, LPRE, LLPRE, HPRE, HHPRE, BIGLPRE,
  35         ZTPRE, JPRE,
  36         STOP,
  37         PTR, INT, UINT, ULLONG,
  38 #ifndef LONG_IS_INT
  39         LONG, ULONG,
  40 #else
  41 #define LONG INT
  42 #define ULONG UINT
  43 #endif
  44         SHORT, USHORT, CHAR, UCHAR,
  45 #ifdef ODD_TYPES
  46         LLONG, SIZET, IMAX, UMAX, PDIFF, UIPTR,
  47 #else
  48 #define LLONG ULLONG
  49 #define SIZET ULONG
  50 #define IMAX LLONG
  51 #define UMAX ULLONG
  52 #define PDIFF LONG
  53 #define UIPTR ULONG
  54 #endif
  55         DBL, LDBL,
  56         NOARG,
  57         MAXSTATE
  58 };
  59
  60 #define S(x) [(x)-'A']
  61
  62 static const unsigned char states[]['z'-'A'+1] = {
  63         { /* 0: bare types */
  64                 S('d') = INT, S('i') = INT,
  65                 S('o') = UINT, S('u') = UINT, S('x') = UINT, S('X') = UINT,
  66                 S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL,
  67                 S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL,
  68                 S('c') = CHAR, S('C') = INT,
  69                 S('s') = PTR, S('S') = PTR, S('p') = UIPTR, S('n') = PTR,
  70                 S('m') = NOARG,
  71                 S('l') = LPRE, S('h') = HPRE, S('L') = BIGLPRE,
  72                 S('z') = ZTPRE, S('j') = JPRE, S('t') = ZTPRE,
  73         }, { /* 1: l-prefixed */
  74                 S('d') = LONG, S('i') = LONG,
  75                 S('o') = ULONG, S('u') = ULONG, S('x') = ULONG, S('X') = ULONG,
  76                 S('c') = INT, S('s') = PTR, S('n') = PTR,
  77                 S('l') = LLPRE,
  78         }, { /* 2: ll-prefixed */
  79                 S('d') = LLONG, S('i') = LLONG,
  80                 S('o') = ULLONG, S('u') = ULLONG,
  81                 S('x') = ULLONG, S('X') = ULLONG,
  82                 S('n') = PTR,
  83         }, { /* 3: h-prefixed */
  84                 S('d') = SHORT, S('i') = SHORT,
  85                 S('o') = USHORT, S('u') = USHORT,
  86                 S('x') = USHORT, S('X') = USHORT,
  87                 S('n') = PTR,
  88                 S('h') = HHPRE,
  89         }, { /* 4: hh-prefixed */
  90                 S('d') = CHAR, S('i') = CHAR,
  91                 S('o') = UCHAR, S('u') = UCHAR,
  92                 S('x') = UCHAR, S('X') = UCHAR,
  93                 S('n') = PTR,
  94         }, { /* 5: L-prefixed */
  95                 S('e') = LDBL, S('f') = LDBL, S('g') = LDBL, S('a') = LDBL,
  96                 S('E') = LDBL, S('F') = LDBL, S('G') = LDBL, S('A') = LDBL,
  97                 S('n') = PTR,
  98         }, { /* 6: z- or t-prefixed (assumed to be same size) */
  99                 S('d') = PDIFF, S('i') = PDIFF,
 100                 S('o') = SIZET, S('u') = SIZET,
 101                 S('x') = SIZET, S('X') = SIZET,
 102                 S('n') = PTR,
 103         }, { /* 7: j-prefixed */
 104                 S('d') = IMAX, S('i') = IMAX,
 105                 S('o') = UMAX, S('u') = UMAX,
 106                 S('x') = UMAX, S('X') = UMAX,
 107                 S('n') = PTR,
 108         }
 109 };
 110
 111 #define OOB(x) ((unsigned)(x)-'A' > 'z'-'A')
 112
 113 union arg
 114 {
 115         uintmax_t i;
 116         long double f;
 117         void *p;
 118 };
 119
 120 static void pop_arg(union arg *arg, int type, va_list *ap)
 121 {
 122         /* Give the compiler a hint for optimizing the switch. */
 123         if ((unsigned)type > MAXSTATE) return;
 124         switch (type) {
 125                case PTR:        arg->p = va_arg(*ap, void *);
 126         break; case INT:        arg->i = va_arg(*ap, int);
 127         break; case UINT:       arg->i = va_arg(*ap, unsigned int);
 128 #ifndef LONG_IS_INT
 129         break; case LONG:       arg->i = va_arg(*ap, long);
 130         break; case ULONG:      arg->i = va_arg(*ap, unsigned long);
 131 #endif
 132         break; case ULLONG:     arg->i = va_arg(*ap, unsigned long long);
 133         break; case SHORT:      arg->i = (short)va_arg(*ap, int);
 134         break; case USHORT:     arg->i = (unsigned short)va_arg(*ap, int);
 135         break; case CHAR:       arg->i = (signed char)va_arg(*ap, int);
 136         break; case UCHAR:      arg->i = (unsigned char)va_arg(*ap, int);
 137 #ifdef ODD_TYPES
 138         break; case LLONG:      arg->i = va_arg(*ap, long long);
 139         break; case SIZET:      arg->i = va_arg(*ap, size_t);
 140         break; case IMAX:       arg->i = va_arg(*ap, intmax_t);
 141         break; case UMAX:       arg->i = va_arg(*ap, uintmax_t);
 142         break; case PDIFF:      arg->i = va_arg(*ap, ptrdiff_t);
 143         break; case UIPTR:      arg->i = (uintptr_t)va_arg(*ap, void *);
 144 #endif
 145         break; case DBL:        arg->f = va_arg(*ap, double);
 146         break; case LDBL:       arg->f = va_arg(*ap, long double);
 147         }
 148 }
 149
 150 static void out(FILE *f, const wchar_t *s, size_t l)
 151 {
 152         while (l-- && !(f->flags & F_ERR)) fputwc(*s++, f);
 153 }
 154
 155 static int getint(wchar_t **s) {
 156         int i;
 157         for (i=0; iswdigit(**s); (*s)++) {
 158                 if (i > INT_MAX/10U || **s-'0' > INT_MAX-10*i) i = -1;
 159                 else i = 10*i + (**s-'0');
 160         }
 161         return i;
 162 }
 163
 164 static const char sizeprefix['y'-'a'] = {
 165 ['a'-'a']='L', ['e'-'a']='L', ['f'-'a']='L', ['g'-'a']='L',
 166 ['d'-'a']='j', ['i'-'a']='j', ['o'-'a']='j', ['u'-'a']='j', ['x'-'a']='j',
 167 ['p'-'a']='j'
 168 };
 169
 170 static int wprintf_core(FILE *f, const wchar_t *fmt, va_list *ap, union arg *nl_arg, int *nl_type)
 171 {
 172         wchar_t *a, *z, *s=(wchar_t *)fmt;
 173         unsigned l10n=0, fl;
 174         int w, p, xp;
 175         union arg arg;
 176         int argpos;
 177         unsigned st, ps;
 178         int cnt=0, l=0;
 179         int i;
 180         int t;
 181         char *bs;
 182         char charfmt[16];
 183         wchar_t wc;
 184
 185         for (;;) {
 186                 /* This error is only specified for snprintf, but since it's
 187                  * unspecified for other forms, do the same. Stop immediately
 188                  * on overflow; otherwise %n could produce wrong results. */
 189                 if (l > INT_MAX - cnt) goto overflow;
 190
 191                 /* Update output count, end loop when fmt is exhausted */
 192                 cnt += l;
 193                 if (!*s) break;
 194
 195                 /* Handle literal text and %% format specifiers */
 196                 for (a=s; *s && *s!='%'; s++);
 197                 for (z=s; s[0]=='%' && s[1]=='%'; z++, s+=2);
 198                 if (z-a > INT_MAX-cnt) goto overflow;
 199                 l = z-a;
 200                 if (f) out(f, a, l);
 201                 if (l) continue;
 202
 203                 if (iswdigit(s[1]) && s[2]=='$') {
 204                         l10n=1;
 205                         argpos = s[1]-'0';
 206                         s+=3;
 207                 } else {
 208                         argpos = -1;
 209                         s++;
 210                 }
 211
 212                 /* Read modifier flags */
 213                 for (fl=0; (unsigned)*s-' '<32 && (FLAGMASK&(1U<<*s-' ')); s++)
 214                         fl |= 1U<<*s-' ';
 215
 216                 /* Read field width */
 217                 if (*s=='*') {
 218                         if (iswdigit(s[1]) && s[2]=='$') {
 219                                 l10n=1;
 220                                 nl_type[s[1]-'0'] = INT;
 221                                 w = nl_arg[s[1]-'0'].i;
 222                                 s+=3;
 223                         } else if (!l10n) {
 224                                 w = f ? va_arg(*ap, int) : 0;
 225                                 s++;
 226                         } else goto inval;
 227                         if (w<0) fl|=LEFT_ADJ, w=-w;
 228                 } else if ((w=getint(&s))<0) goto overflow;
 229
 230                 /* Read precision */
 231                 if (*s=='.' && s[1]=='*') {
 232                         if (isdigit(s[2]) && s[3]=='$') {
 233                                 nl_type[s[2]-'0'] = INT;
 234                                 p = nl_arg[s[2]-'0'].i;
 235                                 s+=4;
 236                         } else if (!l10n) {
 237                                 p = f ? va_arg(*ap, int) : 0;
 238                                 s+=2;
 239                         } else goto inval;
 240                         xp = (p>=0);
 241                 } else if (*s=='.') {
 242                         s++;
 243                         p = getint(&s);
 244                         xp = 1;
 245                 } else {
 246                         p = -1;
 247                         xp = 0;
 248                 }
 249
 250                 /* Format specifier state machine */
 251                 st=0;
 252                 do {
 253                         if (OOB(*s)) goto inval;
 254                         ps=st;
 255                         st=states[st]S(*s++);
 256                 } while (st-1<STOP);
 257                 if (!st) goto inval;
 258
 259                 /* Check validity of argument type (nl/normal) */
 260                 if (st==NOARG) {
 261                         if (argpos>=0) goto inval;
 262                 } else {
 263                         if (argpos>=0) nl_type[argpos]=st, arg=nl_arg[argpos];
 264                         else if (f) pop_arg(&arg, st, ap);
 265                         else return 0;
 266                 }
 267
 268                 if (!f) continue;
 269                 t = s[-1];
 270                 if (ps && (t&15)==3) t&=~32;
 271
 272                 switch (t) {
 273                 case 'n':
 274                         switch(ps) {
 275                         case BARE: *(int *)arg.p = cnt; break;
 276                         case LPRE: *(long *)arg.p = cnt; break;
 277                         case LLPRE: *(long long *)arg.p = cnt; break;
 278                         case HPRE: *(unsigned short *)arg.p = cnt; break;
 279                         case HHPRE: *(unsigned char *)arg.p = cnt; break;
 280                         case ZTPRE: *(size_t *)arg.p = cnt; break;
 281                         case JPRE: *(uintmax_t *)arg.p = cnt; break;
 282                         }
 283                         continue;
 284                 case 'c':
 285                         fputwc(btowc(arg.i), f);
 286                         l = 1;
 287                         continue;
 288                 case 'C':
 289                         fputwc(arg.i, f);
 290                         l = 1;
 291                         continue;
 292                 case 'S':
 293                         a = arg.p;
 294                         z = a + wcsnlen(a, p<0 ? INT_MAX : p);
 295                         if (p<0 && *z) goto overflow;
 296                         p = z-a;
 297                         if (w<p) w=p;
 298                         if (!(fl&LEFT_ADJ)) fprintf(f, "%*s", w-p, "");
 299                         out(f, a, p);
 300                         if ((fl&LEFT_ADJ)) fprintf(f, "%*s", w-p, "");
 301                         l=w;
 302                         continue;
 303                 case 'm':
 304                         arg.p = strerror(errno);
 305                 case 's':
 306                         if (!arg.p) arg.p = "(null)";
 307                         bs = arg.p;
 308                         for (i=l=0; l<(p<0?INT_MAX:p) && (i=mbtowc(&wc, bs, MB_LEN_MAX))>0; bs+=i, l++);
 309                         if (i<0) return -1;
 310                         if (p<0 && *bs) goto overflow;
 311                         p=l;
 312                         if (w<p) w=p;
 313                         if (!(fl&LEFT_ADJ)) fprintf(f, "%*s", w-p, "");
 314                         bs = arg.p;
 315                         while (l--) {
 316                                 i=mbtowc(&wc, bs, MB_LEN_MAX);
 317                                 bs+=i;
 318                                 fputwc(wc, f);
 319                         }
 320                         if ((fl&LEFT_ADJ)) fprintf(f, "%*s", w-p, "");
 321                         l=w;
 322                         continue;
 323                 }
 324
 325                 if (xp && p<0) goto overflow;
 326                 snprintf(charfmt, sizeof charfmt, "%%%s%s%s%s%s*.*%c%c",
 327                         "#"+!(fl & ALT_FORM),
 328                         "+"+!(fl & MARK_POS),
 329                         "-"+!(fl & LEFT_ADJ),
 330                         " "+!(fl & PAD_POS),
 331                         "0"+!(fl & ZERO_PAD),
 332                         sizeprefix[(t|32)-'a'], t);
 333
 334                 switch (t|32) {
 335                 case 'a': case 'e': case 'f': case 'g':
 336                         l = fprintf(f, charfmt, w, p, arg.f);
 337                         break;
 338                 case 'd': case 'i': case 'o': case 'u': case 'x': case 'p':
 339                         l = fprintf(f, charfmt, w, p, arg.i);
 340                         break;
 341                 }
 342         }
 343
 344         if (f) return cnt;
 345         if (!l10n) return 0;
 346
 347         for (i=1; i<=NL_ARGMAX && nl_type[i]; i++)
 348                 pop_arg(nl_arg+i, nl_type[i], ap);
 349         for (; i<=NL_ARGMAX && !nl_type[i]; i++);
 350         if (i<=NL_ARGMAX) return -1;
 351         return 1;
 352
 353 inval:
 354         errno = EINVAL;
 355         return -1;
 356 overflow:
 357         errno = EOVERFLOW;
 358         return -1;
 359 }
 360
 361 int vfwprintf(FILE *restrict f, const wchar_t *restrict fmt, va_list ap)
 362 {
 363         va_list ap2;
 364         int nl_type[NL_ARGMAX] = {0};
 365         union arg nl_arg[NL_ARGMAX];
 366         int olderr;
 367         int ret;
 368
 369         /* the copy allows passing va_list* even if va_list is an array */
 370         va_copy(ap2, ap);
 371         if (wprintf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) {
 372                 va_end(ap2);
 373                 return -1;
 374         }
 375
 376         FLOCK(f);
 377         fwide(f, 1);
 378         olderr = f->flags & F_ERR;
 379         f->flags &= ~F_ERR;
 380         ret = wprintf_core(f, fmt, &ap2, nl_arg, nl_type);
 381         if (f->flags & F_ERR) ret = -1;
 382         f->flags |= olderr;
 383         FUNLOCK(f);
 384         va_end(ap2);
 385         return ret;
 386 }